Longwall Mining Method and Design
Studies estimate that 156 billion tons of coal, representing 68 pct of the minable reserves in the United States, is subject to multiple-seam mining. Historically, room-and-pillar mining has dominated coal production, and this mining method has been the focus of most multiple-seam research. Advances in Longwall Mining Method have made this system more economically attractive […]
Grouted Rock Bolting Procedure
Since the introduction of rock bolts 40 years ago, their use to support and stabilize openings in U.S. mines has steadily increased. The number of roof falls has been significantly reduced where rock bolts have been installed, and they are now the primary support required by the Mine Safety and Health Administration (MSHA) in most […]
Cut Off Grade Calculation Optimization
Cutoff grade is defined as the grade that is normally used to discriminate between ore and waste within a given orebody. Although the definition of cutoff grade is very precise, the choice of a cutoff grade policy to be used during an exploitation of a deposit is not. Use of simply calculated breakeven cutoff grades […]
Mine Dewatering System Design
Dewatering of a surface or underground mine can be a significant production cost. Total costs include both the capital costs for wells, pumps, and water-disposal facilities and the operating costs for pumping, treatment and disposal of the water. Such costs are minimized when the present value of the capital and operating costs is minimized. The […]
Mining Equipment: Select, Buy & Maintain
Mining Equipment Selection Some basic parameters had to be defined at the time: Mechanical or diesel electric trucks. Number of shovels versus size versus number of pits in operation. Size (height and width) of shops and doors. Number of repair bays. Cranes capacity. Number of service equipments (graders, dozers, loaders). The maintenance shop was designed […]
Dragline Mining & Reclamation Mining
The unique application of a large walking dragline in the mountains of southern West Virginia was developed and implemented by Hobet Mining, Inc. Hobet is an independent operating subsidiary of Ashland Coal and is headquartered at the No. 21 Mine in Boone County, West Virginia, near Danville. Hobet also operates the 07 Mine located in […]
Puerto Rico Mining & Precious Metal Mineralization
Mining has never been a major source of income for Puerto Rico. The Spaniards mined gold placer deposits during 1509-1579, and extracted an estimated 1,200,000 troy ounces of gold. However, economics at the time discouraged further mining, and richer sources of gold and silver had been found elsewhere in the New World. The labor source, […]
Blast Hole Liner
Designed to provide quick, hassle free lining of blast holes on the go. Blast Hole Liners are securely packaged in convenient size packs which can be easily transported on site. Dispensing of liners down blast holes takes place speedily and effectively. Durable polyethylene material is abrasion resistant and watertight. Unique packaging method allows for efficient […]
Rock Stability Tester
Aid mine workers in detecting hazardous roof conditions in underground mines by developing a method of roof sounding which supplements or replaces the traditional roof sounding technique where the miner relies on experience to determine whether or not the rock is sound. The Bureau of Mines developed an electronic roof sounding device that acoustically determines […]
Rock Cutting Equipment
Mechanical excavators were introduced for soft rock cutting at the time of the industrial revolution. The early machines date back to mid 1800’s and were developed for rapid excavation of tunnels and to increase production in the mining environment. The early radial or drag type tools were very primitive and made of hardened steel and […]